HCL method for Fe2+estimation to resolve iron chlorosis in plants

Abstract

Abstract The equation dictates that acid solutions should not cause reduction of Fe3+ during extraction of Fe2+ from plants and provide the possibility to preferentially extract Fe2+. Both in vitro and in vivo extraction of Fe2+ with 1N HCl did not cause reduction of Fe3+. Two g chopped fresh plant was reacted with 0.5 to 1.5N HCl and 1:5 to 1:10 tissue:extractant ratios for 24 h. The Fe2+ and Fe3+ in buffered filterates (pH 3.0) were determined with 1–10 o‐phenanthroline (o‐Ph). 1N HCl and 1:10 ratio resolved better the Fe2+ differences between green and iron‐chlorotic plants. Fe2+ iron in chlorotic as compared to non‐chlorotic leaves of different crops was 30 to 82%. This method resolved better or equally good, the visible iron chlorosis in plants, compared to o‐Ph method and is much cheaper. The method also eliminates the inherent error arising from extraction of pigments.